Anatomical imaging system with centipede belt drive

ABSTRACT

An imaging system including a scanner and a transport mechanism mounted to the base of the scanner, wherein the transport mechanism includes a gross movement mechanism for transporting the scanner relatively quickly across room distances and a fine movement mechanism for moving the scanner precisely, relative to the object being scanned, during scanning.

REFERENCE TO PENDING PRIOR PATENT APPLICATIONS

This patent application is a continuation of prior U.S. patentapplication Ser. No. 15/819,355, filed Nov. 21, 2017 by NeuroLogicaCorp. for ANATOMICAL IMAGING SYSTEM WITH CENTIPEDE BELT DRIVE, which inturn is a continuation of prior U.S. patent application Ser. No.14/689,399, filed Apr. 17, 2015 by NeuroLogica Corp. for ANATOMICALIMAGING SYSTEM WITH CENTIPEDE BELT DRIVE, which in turn is acontinuation of prior U.S. patent application Ser. No. 13/593,668, filedAug. 24, 2012 by Andrew P. Tybinkowski et al. for ANATOMICAL IMAGINGSYSTEM WITH CENTIPEDE BELT DRIVE, which in turn is a continuation ofprior U.S. patent application Ser. No. 12/655,360, filed Dec. 29, 2009by Andrew P. Tybinkowski et al. for ANATOMICAL IMAGING SYSTEM WITHCENTIPEDE BELT DRIVE, which in turn is a continuation of prior U.S.patent application Ser. No. 11/706,133, filed Feb. 13, 2007 by Andrew P.Tybinkowski et al. for ANATOMICAL IMAGING SYSTEM WITH CENTIPEDE BELTDRIVE, which in turn is a continuation of prior U.S. patent applicationSer. No. 11/193,941, filed Jul. 29, 2005 by Andrew P. Tybinkowski et al.for ANATOMICAL IMAGING SYSTEM WITH CENTIPEDE BELT DRIVE, which in turnclaims benefit of:

-   -   (i) prior U.S. Provisional Patent Application Ser. No.        60/670,164, filed Apr. 11, 2005 by Andrew P. Tybinkowski et al.        for ANATOMICAL IMAGING SYSTEM WITH CENTIPEDE DRIVE; and    -   (ii) prior U.S. Provisional Patent Application Ser. No.        60/593,001, filed Jul. 30, 2004 by Bernard Gordon et al. for        ANATOMICAL SCANNING SYSTEM.

The eight (8) above-identified patent applications are herebyincorporated herein by reference.

FIELD OF THE INVENTION

This invention relates to anatomical imaging systems in general, andmore particularly to anatomical imaging systems of the sort utilizingComputerized Tomography (CT) systems and the like.

BACKGROUND OF THE INVENTION

Strokes are the third leading cause of death in the United States(causing approximately 177,000 deaths per year) and the number one causeof long-term disability (affecting nearly 5 million people). Strokesresult from abrupt damage to the brain or spinal cord caused by anabnormality of the blood supply.

Strokes typically occur in one of two forms: (i) hemorrhagic, whichoccurs with the rupture of a blood vessel; and (ii) ischemic, whichoccurs with the obstruction of a blood vessel.

Rapid diagnosis is a key component of stroke management. This is becausetreatments for ischemic strokes may be contra-indicated for treatment ofhemorrhagic strokes and, furthermore, the effectiveness of a particulartreatment can be time-sensitive. In particular, the only approvedtherapy for acute ischemic strokes, i.e., the administration of tPA toeliminate clots, is contra-indicated for hemorrhagic strokes.Furthermore, tPA is most effective if it is administered within 3 hoursof the onset of an ischemic stroke. However, current diagnosis times(i.e., the time needed to identify that the patient is suffering from astroke and to identify the hemorrhagic or ischemic nature of the stroke)frequently exceeds this 3 hour window. As a result, only a fraction ofischemic stroke victims are properly treated with tPA.

Imaging is generally necessary to: (i) distinguish strokes from otherconditions; (ii) distinguish between the different types of strokes(i.e., hemorrhagic or ischemic); and (ii) determine suitable treatments.Computerized Tomography (CT) has emerged as the key imaging modality inthe diagnosis of strokes. CT scans, including Non-Enhanced CT, CTangiography and CT perfusion, provide the necessary and sufficientinformation for diagnosing and treating strokes.

Unfortunately, however, the “round-trip” time between the emergency room(where the patient is typically first received) and the radiologydepartment (where the CT machine is typically located) can frequentlytake up to several hours, even in the best hospitals. As a result, thetime spent in transporting the patient from the emergency room to the CTmachine and back again can consume critical time which can compromisetreatment of the patient.

Thus, there is a need for a new and improved CT machine which isparticularly well suited for use in stroke applications.

SUMMARY OF THE INVENTION

The present invention comprises a new and improved anatomical imagingsystem which addresses the foregoing problems. More particularly, thepresent invention comprises a small, mobile CT machine that can be movedto the patient so that the patient can be scanned at their currentlocation, thus dramatically reducing diagnostic times. The mobile CTmachine can be located in the emergency room, is easy to transportdirectly to the patient's bedside, and provides image quality favorablycomparable to traditional, fixed-location CT machines which requirepatient transport.

In essence, the new CT machine eliminates traditional transportationdelays by allowing patients to be scanned in the emergency room, whileremaining on their gurney.

More particularly, with a conventional CT machine, the CT machine isfixed in place, typically in the radiology department. The patient ismoved to the CT machine, placed on a precision-advancement patientplatform and then, with the scanning apparatus remaining stationary, thepatient is advanced into the scanning zone of the CT machine using theprecision-advancement patient platform. In contrast, with new CT machineof the present invention, the patient remains in the emergency room ontheir gurney, the CT machine is moved to the patient and then, while thepatient remains stationary, the CT machine is precision-advancedrelative to the patient so that the scanning zone of the CT machinemoves relative to the patient. Thus, the new CT machine of the presentinvention can be wheeled into position in an emergency room and thepatient scanned while remaining on their gurney, without ever having tomove the patient from the emergency room to the radiology department,and then off the gurney and onto the moving platform of a traditional,fixed-location CT machine.

As a consequence of this novel approach to CT scanning, the new CTmachine requires a precision-advancement mechanism for moving the entireCT machine relative to the patient during the scanning process.

To this end, the present invention provides a novel centipede belt drivewhich provides high precision movement of the CT machine relative to thepatient during scanning. In particular, the centipede belt drive isdesigned to provide substantially the same degree of precision whenmoving the CT machine about the patient as conventional CT machinesprovide when moving the precision-advancement patient platform relativeto the fixed scanning zone of the conventional CT machine.

Preferably the novel CT machine comprises two transport mechanisms: onefor moving the CT machine relatively quickly across room distances priorto scanning, and one for moving the CT machine precisely relative to thepatient during scanning.

In one preferred form of the invention, there is provided an anatomicalimaging system comprising:

a CT machine; and

a transport mechanism mounted to the base of the CT machine, wherein thetransport mechanism comprises a fine movement mechanism for moving theCT machine precisely, relative to the patient, during scanning.

In another preferred form of the invention, there is provided ananatomical imaging system comprising:

a CT machine; and

a transport mechanism mounted to the base of the CT machine, wherein thetransport mechanism comprises:

-   -   a gross movement mechanism for transporting the CT machine        relatively quickly across room distances; and    -   a fine movement mechanism for moving the CT machine precisely,        relative to the patient, during scanning.

In another preferred form of the invention, there is provided an imagingsystem comprising:

a scanner; and

a transport mechanism mounted to the base of the scanner, wherein thetransport mechanism comprises:

-   -   a gross movement mechanism for transporting the scanner        relatively quickly across room distances; and    -   a fine movement mechanism for moving the scanner precisely,        relative to the object being scanned, during scanning.

In another preferred form of the invention, there is provided a methodfor scanning a patient comprising:

providing an anatomical imaging system, the system comprising:

-   -   a CT machine; and    -   a transport mechanism mounted to the base of the CT machine,        wherein the transport mechanism comprises:        -   a gross movement mechanism for transporting the CT machine            relatively quickly across room distances; and        -   a fine movement mechanism for moving the CT machine            precisely, relative to the patient, during scanning;

transporting the CT machine to the patient, across room distances, usingthe gross movement mechanism; and

scanning the patient while moving the CT machine precisely, relative tothe patient, with the fine movement mechanism.

In another preferred form of the invention, there is provided a methodfor scanning a patient, comprising:

moving a CT machine across room distances to the patient; and

scanning the patient while moving the CT machine precisely relative tothe patient during scanning.

In another preferred form of the invention, there is provided a methodfor scanning an object, comprising:

moving a scanner across room distances to the object; and

scanning the object while moving the scanner precisely relative to theobject during scanning.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects and features of the present invention will bemore fully disclosed or rendered obvious by the following detaileddescription of the preferred embodiments of the invention, which are tobe considered together with the accompanying drawings wherein likenumbers refer to like parts, and further wherein:

FIGS. 1-6 are a series of views showing the exterior of a novel CTmachine formed in accordance with the present invention;

FIG. 7 is a bottom view of the CT machine showing its novel transportmechanism;

FIGS. 8-10 show the CT machine's gross movement mechanism and finemovement mechanism secured to the frame of the CT machine;

FIGS. 11-14 show details of the construction of the CT machine's grossmovement mechanism; and

FIGS. 15-25 show details of the construction of the CT machine's finemovement mechanism.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS CT Machine 5

Looking first at FIGS. 1-6, there is shown a novel CT machine 5 formedin accordance with the present invention. CT machine 5 generallycomprises a base 10 which supports a torus 15. Torus 15 defines a centeropening 20. Base 10 and torus 15 together comprise the CT scanningapparatus which is used to scan the patient anatomy positioned in centeropening 20. Such scanning apparatus typically comprises a rotating X-raysource and X-ray detector, and various electronic hardware and softwarefor controlling the apparatus and processing the acquired data so as togenerate the CT scans. Such scanning apparatus may be of the sort wellknown in the art.

CT machine 5 also comprises the novel transport mechanism 100 which willhereinafter be discussed.

Transport Mechanism 100

As noted above, CT machine 5 is intended to be moved to the patient, andthen scan the patient while the patient remains stationary on theirgurney.

To this end, in one preferred form of the invention, and looking now atFIG. 7, CT machine 5 preferably comprises a transport mechanism 100which comprises two different mechanisms for moving CT machine 5: (i) agross movement mechanism 105 for transporting CT machine 5 quicklyacross significant distances (e.g., across a room to the patient); and(ii) a fine movement mechanism 110 for moving CT machine 5 preciselyacross small distances (e.g., relative to the patient during scanning).As will hereinafter be discussed, fine movement mechanism 110 preferablycomprises the aforementioned centipede belt drive for precisely movingthe CT machine relative to the patient during scanning.

As seen in FIGS. 8-10, gross movement mechanism 105 and fine movementmechanism 110 are both secured to the frame 115 of base 10 so that theycan, alternatively, support CT machine 5.

Gross Movement Mechanism 105

Gross movement mechanism 105 is used to transport CT machine 5 quicklyacross significant distances (e.g., across a room to the patient). Moreparticularly, and looking now at FIGS. 8-14, gross movement mechanism105 preferably comprises two identical, spaced-apart caster units 117which cooperate to form the gross movement mechanism 105.

Each caster unit 117 comprises a chassis 120 having a pair of casters125 rotatably mounted thereto. Chassis 120 is movably mounted to asupport block 130, and support block 130 is in turn secured to frame115. More particularly, chassis 120 is movably mounted to support block130 by means of a pair of slide rods 135 and support block 130 areslidably received in slide housings 140 which are secured to supportblock 130. An actuator (hydraulic or otherwise) 145, which is mounted tosupport block 130, has its actuator rod 150 engaging chassis 120. Asnoted above, support block 130 is secured to frame 115 of CT machine 5.

As a result of this construction, when it is desired to move CT machine5 about on gross movement mechanism 105, gross movement mechanism 105 isoperated as follows. The two caster units 117 are operated in acoordinated fashion so that their actuators (hydraulic or otherwise) 145extend their actuator rods 150 so as to cause chassis 120 to projectdownward from support blocks 130, whereby to cause the casters 125 toengage the floor and support CT machine 5 on the casters 125. CT machine5 can then be maneuvered about a room on the casters 125. When it isdesired to use the CT machine 5 for scanning, the gross movementmechanism 105 is operated as follows. The two caster units 117 areoperated in a coordinated fashion so that their actuators (hydraulic orotherwise) 145 retract their actuator reds 150 so as to cause chassis120 to return towards support blocks 130, whereby to seat fine movementmechanism 110 of CT machine 5 securely on the floor.

In one configuration, gross movement mechanism 105 comprises twoidentical caster units 117, with one caster unit 117 located on eachside of the patient. Alternatively, more than two caster units 117 maybe provided (e.g., three or four), and they may be distributed aboutbase 10 of CT machine 5 in any desired configuration.

Fine Movement Mechanism 110

Fine movement mechanism 110 is used to move CT machine 5 preciselyrelative to the patient during scanning. More particularly, and lookingnow at FIGS. 7 and 9, fine movement mechanism 110 preferably comprisestwo identical, spaced-apart centipede belt drive units 153 whichcooperate to form the fine movement mechanism 110.

Looking next at FIGS. 15-25, each centipede belt drive unit 153comprises a chassis 155 which is secured to frame 115. Chassis 155preferably comprises two halves (FIG. 18) which are secured together toform a single housing with an interior space. Chassis 155 has a belt 160drivably mounted thereto. More particularly, chassis 155 comprises apair of drive gears (sometimes referred to as a timing pulley) 165 whichare rotatably mounted to chassis 155. Drive gears 165 comprise teeth 170which engage counterpart ribs (not shown) formed on the interior of belt160, such that when drive gears 165 are rotated, their rotational motionis transferred to belt 160. Preferably teeth 170 have an archedconfiguration, so as to provide a uniform engagement between adjacentteeth and the drive belt, thereby allowing precision transfer of motionbetween the drive gear and the drive belt. One or more motors 175 aresecured to chassis 155. Preferably motors 175 are located inside thecentipede belt drive unit to save space. A transmission belt 180connects the drive shaft of motor 175 to at least one of the drive gears165, whereby the one or more motors 175 can be used to turn belt 160 andthereby drive the unit.

A suspension unit 185, such as the one shown in FIGS. 18-25, or anothersuspension unit of the sort well known in the belt drive art, ispreferably secured to chassis 155 within the interior of belt 160 so asto distribute the load of CT machine 5 across a plurality of rollers andonto the belt 160. In one preferred construction, suspension unit 185comprises (FIGS. 21-25) a pair of roller assemblies 190 balanced with apair of rockers 195 which are mounted on an axle 200 and balanced withfour springs 205.

Additional suspension rollers (e.g., rollers 210 in FIGS. 18-20) mayalso be provided if desired.

As a result of this construction, when it is desired to move CT machine5 on fine movement mechanism 110, CT machine 5 is lowered onto finemovement mechanism 105 (i.e., by retracting the casters 125 of grossmovement mechanism 105), and then fine movement mechanism 110 isoperated as follows. The two centipede belt drive units 153 are operatedin a coordinated fashion so that their motors 175 rotate drive gears165, whereby to turn belts 160 and thereby precisely advance CT machine5 (e.g., relative to a patient).

The centipede belt drive unit 153 is designed to move the CT machinerelative to the patient in one of two motions: (1) indexed movementusing discrete steps for slice scanning; and (2) smooth movement usingsubstantially continuous motion for helical scanning. The centipede beltdrive unit 153 achieves this through the use of the aforementionedfloor-engaging drive belts 160 which provide the necessary precisionmovement and repeatability

The centipede belt drive system is preferably configured to allowmulti-directional patient scanning, i.e., scanning in both forward andbackward directions.

In a preferred embodiment of the invention, two independent centipedebelt drive units 153 are used, one on each side of the patient. The twocentipede belt drive units are driven in a coordinated fashion so as toeffect the precise movement desired. In this respect it should beappreciated that, due to the use of two independent belt drives,differences in components or external conditions (e.g., floor tilt) maycreate a yawing effect. This is resolved by driving each belt separatelyat an appropriate rate.

A feedback system is preferably used to ensure that each centipede beltdrive unit 153 is moving at the desired speed. An encoder device (e.g.,an optical encoder or a rotary potentiometer or other device) may beused to determine the rate of drive gear movement so as to regulate beltmovement. In this respect it should be appreciated that, in view of thevery small movements associated with CT scanning, hysteresis problemsmay arise with the drive belts 160. The encoder device may also be usedto identify and compensate for any such hysteresis.

In one configuration, the fine movement mechanism 105 comprises twoidentical centipede belt drive units 153, with the two identical drivesstraddling the patient. Alternatively, the CT machine could be providedwith wheels on each side of the patient, and a single centipede beltdrive unit 153 could be provided to move the wheeled assembly duringscanning movement.

Use

In accordance with the present invention, transport mechanism 100 can beused to move CT machine 5 as follows. Initially, CT machine 5 is raisedon its gross movement mechanism 105 by causing actuators (hydraulic orotherwise) 145 to extend their actuator rods 150, whereby to causecasters 125 to engage the floor and support CT machine 5 on the casters125. CT machine 5 can then toe maneuvered about a room on its casters125, i.e., so that a patient lying on a gurney may be positioned withinthe center opening 20 of CT machine 5 without moving the patient off thegurney. Thereafter, gross movement mechanism 105 is operated so that thecaster units 117 retract their actuator rods 150 so as to cause chassis120 to return towards their support blocks 130, whereby to permit thedrive belts 160 of fine movement mechanism 110 to engage the floor.Thereafter, when scanning is commenced, motors 175 are used to preciselyadvance belt 160, and hence CT machine 5, relative to the patient duringscanning.

Thus, in one preferred form of the invention, the fine movementmechanism 110 operates only during the scanning process. Moreparticularly, prior to scanning, the CT machine is moved to the patienton gross movement mechanism 105; thereafter, the fine movement mechanism105 engages the floor and operates during scanning to move the CTmachine relative to the patient during the scanning process.Alternatively, where fine movement mechanism 110 is capable ofreasonably rapid rates of speed, gross movement mechanism 105 may beomitted entirely and only fine movement mechanism 110 provided.

Application to Other Types of Scanning Systems

It should be appreciated that the present invention is not limited touse in medical applications or, indeed, to use with CT machines. Thus,for example, the present invention may be used in connection with CTmachines used for non-medical applications, e.g., with CT machines usedto scan inanimate objects. Furthermore, the present invention may beused with non-CT-type scanning systems. In essence, the presentinvention has application to any scanning device which requires that thescanning apparatus be precisely moved relative to the scanned object.Thus, for example, the present invention may be used in conjunction withother types of scanners.

MODIFICATIONS

It will be appreciated that still further embodiments of the presentinvention will be apparent to those skilled in the art in view of thepresent disclosure. It is to be understood that the present invention isby no means limited to the particular constructions herein disclosedand/or shown in the drawings, but also comprises any modifications orequivalents within the scope of the invention.

What is claimed is:
 1. An anatomical imaging system comprising: a CTmachine; and a transport mechanism mounted to the CT machine, whereinthe transport mechanism comprises a fine movement mechanism for movingthe CT machine precisely, relative to a patient, during scanning, andfurther wherein the fine movement mechanism is configured to directlyengage and move along the floor so as to move the CT machine.
 2. Asystem according to claim 1 wherein the fine movement mechanism isconfigured to move the CT machine relative to the patient using indexedmovement in discrete steps, whereby to enable slice scanning.
 3. Asystem according to claim 1 wherein the fine movement mechanism isconfigured to move the CT machine relative to the patient usingsubstantially continuous movement, whereby to enable helical scanning.4. A method for scanning a patient, comprising: moving a CT machineacross room distances to the patient; and scanning the patient whilemoving the CT machine precisely, relative to the patient, duringscanning, wherein the CT machine is moved during scanning with amovement mechanism that directly engages and moves along the floor tomove the CT machine.
 5. A method according to claim 4 wherein themovement mechanism is configured to move the CT machine relative to thepatient using indexed movement in discrete steps, whereby to enableslice scanning.
 6. A method according to claim 4 wherein the movementmechanism is configured to move the CT machine relative to the patientusing substantially continuous movement, whereby to enable helicalscanning.
 7. A method for scanning an object, comprising: moving ascanner across room distances to the object; and scanning the objectwhile moving the scanner precisely, relative to the object, duringscanning, wherein the scanner is moved during scanning with a movementmechanism that directly engages and moves along the floor to move thescanner.
 8. A method according to claim 7 wherein the movement mechanismis configured to move the scanner relative to the object using indexedmovement in discrete steps, whereby to enable slice scanning.
 9. Amethod according to claim 7 wherein the movement mechanism is configuredto move the scanner relative to the object using substantiallycontinuous movement, whereby to enable helical scanning.